The present invention relates generally to latch mechanisms for use in access devices, and more specifically, to an improved latch mechanism for facilitating installation and proper engagement between the latchbolt and strike.
A latchbolt or latch bolt is a common latch type, typically part of a lockset, comprising a spring-loaded bolt with an angled edge. When a door is closed, the angled edge of the latchbolt engages with the lip of a strike plate. A spring allows the bolt to retract, and once the door is fully closed, the bolt automatically extends into the strike plate. Typically, the latchbolt is disengaged or retracted when a user turns a door handle which, via the lockset's mechanism, manually retracts the latchbolt, allowing the door to open.
Vertical rod door latches are door latches commonly used in commercial or public buildings where the door latches are located at the top and/or bottom edge of the door. Vertical rod door latches typically include one or more latches or catches that extend upward out of the top and/or downward from the bottom edge of the door into a corresponding opening in a strike located in the door frame above the door or on the floor below the door.
The latches are most commonly driven into and out of engagement with the corresponding strike by vertical rods extending from an actuator located near the midpoint of the door to the top and/or bottom latches. The vertical rods extending from the actuator may be hidden inside the door or located on the surface of the door and they may drive the latches at each point with either a pulling or pushing motion. For a glass door, the vertical rod and actuator is typically concealed in push/pull bar or rail extending along at least a portion of the length of the glass panel.
The actuator most commonly used to drive the latch points of a vertical rod door latch includes a lever handle, or a pushbar or pushrail type exit device. An “exit device” is a lock mechanism operated from the inside of an exit door through the use of a crossbar, pushbar, pushrail, panic bar or paddle actuator that moves towards the exit door to retract the latchbolt when pressure is applied.
Typically, the depth of latch projection into the strike is set before a door is installed and final adjustments require the door to be taken down and re-adjusted, then installed again. Installation and proper engagement between the latchbolt and strike can be problematic, particularly in latch mechanisms used in exit devices for glass doors. If the latchbolt protrudes too far into the strike, too much force may be required to retract the latch. Conversely, if the latchbolt does not protrude far enough into the strike, it may be possible to open the door with sufficient force, even if the latch is not retracted. Moreover, with respect to glass panel doors, typical latchbolt configurations can result in additional security issues, as the flexibility of the glass under force may result in latchbolt failure.
Therefore, a need exists for an improved latch mechanism for facilitating installation and proper engagement between the latchbolt and the strike.
Bearing in mind the problems and deficiencies of the prior art, it is therefore an object of the present invention to provide an improved latch mechanism for facilitating installation and proper engagement between the latchbolt and the strike.
It is another object of the present invention to provide a latchbolt including a pair of visible indicia on a side thereof, one of the indicia indicating a minimum desired distance of extension of the latchbolt inside the strike plate opening and the other of the indicia indicating a maximum desired distance of extension of the latchbolt inside the strike plate opening.
It is yet another object of the present invention to provide a latchbolt having a non-flat sweep side for contacting an outside surface of a strike plate to cause retraction of the latchbolt, and an opposite flat face for contacting an inside surface of an opening in a face of the strike plate to prevent the door from opening when the latchbolt is extended.
A further object of the present invention is to provide a latchbolt which prevents point contact with the inside of the strike plate opening and reduces the force required to retract the latchbolt when the latchbolt face is in contact with the inside of the strike plate opening.
Still another object of the present invention is to provide a latchbolt that reduces opening and closing forces of the door during contact between the latchbolt and strike plate.
Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification.
The above and other objects, which will be apparent to those skilled in the art, are achieved in the present invention which is directed to a door latch slide for engagement with a strike plate in a doorjamb. The door latch slide comprises a latch slide body engageable with an actuator device mounted on the door for moving the latch slide toward and away from the strike plate, the latch slide body being adjustable with respect to the door to adjust extension distance toward the strike plate, and a latchbolt extending from the latch slide body, the latchbolt having a non-flat sweep side for contacting an outside of the strike plate to cause retraction of the latchbolt away from the strike plate as the door is closing and an opposite flat face for contacting an inside of an opening in a face of the strike plate to prevent the door from opening when the latchbolt is extended toward and into the strike plate opening. The latchbolt has a pair of indicia on a side thereof, one of the indicia indicating a minimum desired distance of extension of the latchbolt inside the strike plate opening and the other of the indicia indicating a maximum desired distance of extension of the latchbolt inside the strike plate opening. The latch slide may be adjusted during installation of the actuator device by visually extending the latchbolt into the strike plate opening, moving the latch slide body toward or away from the strike plate until the strike plate face is between the pair of indicia on the latchbolt, and setting the latch slide body with respect to the actuator device so that the latchbolt when extended maintains the strike plate face between the pair of indicia on the latchbolt.
The latchbolt may have opposite sides between the sweep side and flat face, wherein the indicia is visible on at least one of the opposite sides of the latchbolt. The pair of indicia may comprise visible parallel lines extending perpendicular to direction of movement of the latch slide body, and the visible parallel lines may be engraved in a side of the latchbolt.
In another aspect, the present invention is directed to a method of adjusting a door latch slide for engagement with a strike plate in a doorjamb. The method comprises providing a door latch slide having a latch slide body engageable with an actuator device mounted on the door for moving the latch slide toward and away from the strike plate, the latch slide body being adjustable with respect to the door to adjust extension distance toward the strike plate, and providing a latchbolt extending from the latch slide body, the latchbolt having a non-flat sweep side for contacting an outside of the strike plate to cause retraction of the latchbolt away from the strike plate as the door is closing and an opposite flat face for contacting an inside of an opening in a face of the strike plate to prevent the door from opening when the latchbolt is extended toward and into the strike plate opening, the latchbolt having a pair of indicia on a side thereof, one of the indicia indicating a minimum desired distance of extension of the latchbolt inside the strike plate opening and the other of the indicia indicating a maximum desired distance of extension of the latchbolt inside the strike plate opening. The method further comprises providing an actuator device mounted on the door for moving the latch slide toward and away from the strike plate, installing the door latch slide in the actuator device, and adjusting the latch slide with respect to the actuator device by: visually extending the latchbolt into the strike plate opening, moving the latch slide body toward or away from the strike plate until the strike plate face is between the pair of indicia on the latchbolt, and setting the latch slide body with respect to the actuator device so that the latchbolt when extended maintains the strike plate face between the pair of indicia on the latchbolt.
In still another aspect, the present invention is directed to a door latch slide for engagement with a strike plate in a doorjamb, comprising a latch slide body engageable with an actuator device mounted on the door for moving the latch slide toward and away from the strike plate, and a latchbolt extending from the latch slide body. The latchbolt has a non-flat sweep side for contacting an outside of the strike plate to cause retraction of the latchbolt away from the strike plate as the door is closing, an opposite flat face for contacting an inside of an opening in a face of the strike plate to prevent the door from opening when the latchbolt is extended toward and into the strike plate opening, and opposite sides between the sweep side and flat face. The latchbolt flat face has beveled edges along the latchbolt opposite sides, wherein when the latch slide moves from the door toward the strike plate, and the latchbolt is extended into the strike plate opening, the beveled edges prevent point contact with the inside of the strike plate face opening and reduce force required to retract the latch slide when the latch face is in contact with the inside of the strike plate face opening.
The latchbolt face may be planar and the beveled edges along the opposite sides of the latchbolt face may comprise curved surfaces between the latchbolt face and the latchbolt opposite sides. The latchbolt may further have a curved surface between the end of the latchbolt face and the non-flat sweep side.
The latchbolt may further include a pair of indicia on a side thereof, one of the indicia indicating a minimum desired distance of extension of the Iatchbolt inside the strike plate opening and the other of the indicia indicating a maximum desired distance of extension of the latchbolt inside the strike plate opening.
In still yet another aspect, the present invention is directed to a door latch slide for engagement with a strike plate in a doorjamb, comprising a latch slide body engageable with an actuator device mounted on the door for moving the latch slide toward and away from the strike plate, and a latchbolt extending from the latch slide body, the latchbolt having a non-flat sweep side for contacting an outside of the strike plate to cause retraction of the latchbolt away from the strike plate as the door is closing and an opposite flat face for contacting an inside of an opening in a face of the strike plate to prevent the door from opening when the latchbolt is extended toward and into the strike plate opening. The latchbolt has a first radius at an end thereof between the flat face and the sweep side and a second radius at the sweep side, the second radius being greater than the first radius. The Iatchbolt has a surface between the flat face and the sweep side with a smooth transition between the first and second radii, wherein the latchbolt first and second radii and the smooth surface transition therebetween reduce opening and/or closing forces of the door during contact between the latchbolt and the strike plate.
The features of the invention believed to be novel and the elements characteristic of the invention are set forth with particularity in the appended claims. The figures are for illustration purposes only and are not drawn to scale. The invention itself, however, both as to organization and method of operation, may best be understood by reference to the detailed description which follows taken in conjunction with the accompanying drawings in which:
In describing the embodiments of the present invention, reference will be made herein to
Certain terminology is used herein for convenience only and is not to be taken as a limitation of the invention. For example, words such as “upper,” “lower,” “left,” “right,” “horizontal,” “vertical,” “upward,” and “downward” merely describe the configuration shown in the drawings. For purposes of clarity, the same reference numbers may be used in the drawings to identify similar elements.
Additionally, in the subject description, the word “exemplary” is used to mean serving as an example, instance or illustration. Any aspect or design described herein as “exemplary” is not necessarily intended to be construed as preferred or advantageous over other aspects or design. Rather, the use of the word “exemplary” is merely intended to present concepts in a concrete fashion.
Referring now to
Typically, the depth of latch projection into the strike is set before a door is installed and final adjustments require the door to be taken down and re-adjusted, then installed again. Installation and proper engagement between the latchbolt and strike can be problematic, particularly in latch mechanisms used in exit devices for glass doors. If the latchbolt protrudes too far into the strike, too much force may be required to retract the latch. Conversely, if the latchbolt does not protrude far enough into the strike, it may be possible to open the door with sufficient force, even if the latch is not retracted.
The latch mechanism of the present invention facilitates installation and proper engagement between the latchbolt and strike plate by including a visual indicator to aid the installer. As shown in
Adjustment of the latch mechanism with respect to the actuator device comprises visually extending the latchbolt 12 into the strike plate opening, moving the latch body 10 toward or away from the strike plate until the face of the strike plate is between the pair of indicia 50a, 50b on the latchbolt, and setting the latch body 10 with respect to the actuator device such that, when extended, the latchbolt 12 maintains the face of the strike plate between indicia 50a, 50b.
Referring again to
As shown in
As best shown in
Latchbolt 12 further has a surface 30c at an upper end of the latchbolt between face 30 and sweep side 40 defining a smooth transition between radii R1, R2. Referring now to
Thus, the present invention achieves one or more of the following advantages. The present invention provides an improved latch mechanism for facilitating installation and proper engagement between the latchbolt and the strike, comprising a latchbolt including a pair of visible indicia on at least one side thereof, one of the indicia indicating a minimum desired distance for extension of the latchbolt inside the strike plate opening and the other of the indicia indicating a maximum desired distance for extension. Proper engagement of the latchbolt can be determined by visually extending the latchbolt into the strike plate opening, moving the latch slide body toward or away from the strike plate until the strike plate face is between the pair of indicia on the latchbolt, and setting the latch slide body with respect to the actuator device so that the latchbolt when extended maintains the strike plate face between the pair of indicia on the latchbolt. A non-flat sweep side of the latchbolt contacts an outside surface of a strike plate to cause retraction of the latchbolt as the door is moved toward a closed position, and an opposite flat face contacts an inside surface of an opening in a face of the strike plate to prevent the door from opening when the latchbolt is extended. The latchbolt further has beveled edges between the flat face and the non-flat sweep side which provide non-point contact, over a limited surface area, with the inside of the strike plate opening and reduce the force required to retract the latchbolt when the latchbolt face is in contact with the inside of the strike plate opening.
While the present invention has been particularly described, in conjunction with specific embodiments, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art in light of the foregoing description. It is therefore contemplated that the appended claims will embrace any such alternatives, modifications and variations as falling within the true scope and spirit of the present invention.
This application claims priority to U.S. patent application Ser. No. 62/487,280 filed on Apr. 19, 2017, the entire disclosure of which is incorporated herein by reference.
Number | Date | Country | |
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62487280 | Apr 2017 | US |